The present invention relates to a method and an apparatus for recognizing a smear, and more particularly to a method and an apparatus for automatically recognizing an object smeared in test samples on a slide.
In a prior art method for examining blood cells, it has been common that a skilled examiner visually observes a blood sample smeared on a slide glass by an optical microscope to discover white blood corpuscles and classify them by pattern recognition technique in accordance with shapes and colors of the white blood corpuscles. However, since such a visual method accompanies with the fatigue of the examiner, a long time work is difficult to do and only a small number of samples can be processed. In order to resolve such a problem, an automatic classifying apparatus for white blood corpuscles has been developed. Apparatus for classifying the blood smeared on a slide and observed by a microscope in accordance with the configuration of the blood cells are shown in the U.S. Pat. No. 4,175,859 to A. Hashizume et al, U.S. Pat. No. 3,827,804 to M. N. Miller et al and an article entitled "Leubocyte Pattern Recognition" by J. W. Bacus et al, IEEE Transactions on Systems, Man and Cybernetics, Vol. SMC-2, No. 4, page 513, 1972.
Blood smears to be tested usually have various blood cell distribution densities and conditions on a slide gears depending on the smear condition and it is difficult to prepare samples of a uniform blood cell distribution.
Particularly when the samples are prepared by hand application or an automatic wedge type smear apparatus, the configuration of the blood cell changes from position to position on the slide glass. Accordingly, when such a sample is to be tested, an examiner views each sample through a microscope to find out an area of less change in configuration before the blood cells are automatically classified by the apparatus.